take sniffs is used in a similar fashion as 'lick my nuts' - except instead of suggesting the licking of nuts, take sniffs refers to the sniffing of nuts. its said either as a response to something, or at the end of a sentence to add effect.

"dude - i just had a yums ass pizza all to myself - take sniffs"

or

guy A: "dude...your an a**hole"

guy B: "oh yeah? well you have no friends and masturbate to pokemon puzzle league porno silver edition in your free time so take sniffs"